1. Field of the Invention
In designing the present space shuttle orbiter it is considered essential to provide means for quickly venting the air in the crew cabin on the orbiter should it become necessary for the crew to open an escape hatch in the lower compartment of the cabin and make an emergency evacuation if an abort situation occurs while the orbiter is at a relatively-low altitude. Those skilled in the art will, of course, recognize that unless the lower compartment of the crew cabin is quickly vented, there is a considerable risk of an implosion of the mid-deck of the orbiter vehicle before the crew members in the lower compartment can reach the escape hatch.
To deal with this potentially-dangerous situation, the orbiter is presently equipped with a vent opening in the lower portion of the rear bulkhead of the crew cabin. This vent opening is normally closed by a releasable cover plate that is disposed over the opening and sealingly engaged with the bulkhead for maintaining the pressure-tight integrity of the cabin. An explosive release assembly preferably comprising one or more linear shaped explosive charges is mounted on the forward face of the bulkhead with the linear shaped charges disposed against and directed at the marginal portion of the cover plate. The shaped charges are cooperatively arranged so as to be selectively actuated for quickly separating the cover plate from the bulkhead so as to rapidly exhaust the pressured air from the cabin compartment into the adjacent cargo bay just above the escape hatch is opened. In this manner, the crew can safely abandon the orbiter vehicle without risking an implosion of the intermediate deck in the cabin which might otherwise occur should the escape hatch be opened during the initial stages of the launch or when the orbiter is returning to earth.
Accordingly, the present invention pertains to new and improved apparatus for catching the cover plate when it is blown away from the vent opening of the orbiter as well as for trapping the various fragments caused by the actuation of the explosive release assembly and bringing these rapidly-moving objects to a halt in a relatively limited span of travel. In particular, the invention relates to new and improved compact energy-absorbing apparatus cooperatively arranged for reliably capturing the various elements of an explosively-actuated venting assembly that would be violently propelled therefrom upon the operation of the venting assembly. In this manner, the cover plate as well as broken elements and metal fragments will be halted before they can strike nearby fuel tanks in the cargo bay in the path of this rapidly-moving debris which might otherwise be exploded when impacted by this debris.
2. Background Art
At present it is proposed to construct the NASA space orbiter with an enclosed crew cabin which will be ordinarily maintained at a sufficient pressure that the crew can move freely around the cabin without wearing pressured suits. Nevertheless, provisions must be made to enable the crew to leave the cabin quickly and safely in the event of an emergency. One important aspect of such an emergency procedure is to provide an effective venting assembly for quickly exhausting the air in the crew cabin to prevent implosion of the cabin mid-deck when the crew escape hatch in the lower compartment is opened.